The manipulation of images, for example images which represent faces and or bodies of human subjects, for the purposes of general enhancement of images is known. For example, the processing of images to lessen the visibility of high frequency blemishes and marks is known as airbrushing.
Specific techniques for manipulating the surface properties of images of faces are computationally complex since the way in which skin reflects lighting is not well understood or is otherwise very complex and challenging to model or predict. Accordingly, it is particularly difficult to manipulate or modify the degree, direction, and/or contrast of the lighting in an image in a realistic manner.
Moreover, many techniques for manipulating images require a significant amount of user input and a considerable level of skill or technique to perform. Such manipulation may, for example, take the form of a user-controlled pointer tool which is displayed on the screen and which enables the user to manually manipulate small areas of the image. Such image manipulation methods are time-consuming and require considerable skill or training to perform.
The present invention seeks to provide an improved method of manipulating images in which the processing is performed in an automated manner. As such, the present invention seeks to reduce the amount of time and expertise required by the user in order to manipulate an image. In so doing, the present invention also enables the manipulation of lighting and/or identity characteristics of an image.